yiU CONTENTS. 



CHAPTER IV. 



SPONGID.E. 



Page 

 I. Animal nature 2. Form and Size. — 3. Skeleton, — 4. Aqui- 

 ferous system. — 5. Reparative powers. — 6, Spicula. — 7. 

 Classification. — 8. Structure of Tethya. — 9. Development. 

 — 10, Distribution. — J I. Affinity to Foraminifera - - 30 



CHAPTER V. 



THALASSICOLLIB^. 



I. External characters. — 2. Organisation. — 3. Acanthometrs - 44 



CHAPTER VI. 



GREGARIXID^. 



I. Habit. — 2. Form and Stnictiire. — 3. Development. — 4. Clas- 

 sificaticm. — 5. Psorospermiae - - - - 49 



CHAPTER VII. 



INFUSORIA. 



I. Nature of Infusoria. — 2. Example of the Group : Vorticella. 

 — 3. Classification. — 4. Size. — 5. Form and Structure. — 6. 

 Digestive apparatus. — 7. Contractile vesicle. — 8. Nucleus, 

 &c. — 9. Urticating organs. — 10. Locomotive organs. — 

 II. Development. — 12. Distribution. — 13. Noctiluca -53 



Bibliography of the Protozoa - - - - 79 



Questions on the Protozoa - - - - - 83 



List of Illustrations - - - - - - 85 



Index - - - - - - - - $6 



